Allow specifying custom names for registers


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@7546 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/Target.td b/lib/Target/Target.td
index b55693c..546eeec 100644
--- a/lib/Target/Target.td
+++ b/lib/Target/Target.td
@@ -35,6 +35,14 @@
 //
 class Register {
   string Namespace = "";
+  string Name = "";
+}
+
+// NamedReg - If the name for the 'def' of the register should not become the
+// "name" of the register, you can use this to specify a custom name instead.
+//
+class NamedReg<string n> : Register {
+  set Name = n;
 }
 
 // RegisterAliases - You should define instances of this class to indicate which